[PATCH 5/6] i915: fail atomic commit when muxed away

[Daniel Dadap]

Attempting to commit a modeset while mux-switched away can cause
problems due to DisplayPort links being unavailable while they are
physically disconnected. In order to avoid this, bail out of atomic
commit early if attempted while a display mux is switched away.

Signed-off-by: Daniel Dadap <ddadap at nvidia.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 346846609f45..4ad799e4b024 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -31,6 +31,7 @@
 #include <linux/module.h>
 #include <linux/dma-resv.h>
 #include <linux/slab.h>
+#include <linux/vga_switcheroo.h>
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
@@ -15736,6 +15737,12 @@ static int intel_atomic_commit(struct drm_device *dev,
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	int ret = 0;
 
+	if (!vga_switcheroo_is_client_active(to_pci_dev(dev->dev))) {
+		drm_dbg_atomic(&dev_priv->drm,
+			"Atomic commit attempted while muxed away.\n");
+		return -EINVAL;
+	}
+
 	state->wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
 
 	drm_atomic_state_get(&state->base);
-- 
2.18.4